The definition of an ai is a mammal that is native to Venezuela, the Guianas and northern Brazil that is an herbivore, and is one of only four types of three-toed sloths.(noun)
An example of an ai is a Maned Sloth.
The definition of ai is a word used to express pain or sorrow.(interjection)
An example of when someone would say "ai" is when they hear that their son did not get into graduate school.
See ai in Webster's New World College Dictionary
noun pl. ais
Origin: Tupí ai, hai < the animal's cry
See ai in American Heritage Dictionary 4
Origin: , of Tupian origin.
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